The present invention is directed to a lumbar support air valve assembly and more particularly to a lumbar support air valve assembly for selectively controlling the degree of pressurization of a plurality of air bags located in the lumbar support region of a seat back for controlling the contour thereof to suit individual requirements.
A conventional lumbar support air valve assembly is shown in FIG. 1 of the present application wherein a controlled lock is provided with an inlet port 2 which receives air from a pressurized air source. The air is transmitted to the spaces 1 in the block past the ball check valve 3, air filter 4, check valve 5, chamber 6, check valves 7 and air filters 8. Each space 1 is connected to an inflatable air bag 11, three of which are shown in FIG. 2 by means of suitable pipes so that each air bag receives a supply of pressurized air. When the air pressure within the chamber 6 exceeds a pre-determined value, a regulator valve 9 opens so that the excessive air pressure is relieved through the port 10. Thus, the air pressure within each air bag 11 will not increase above the pre-determined value. Push buttons 13 corresponding to check valves 7, respectively, are provided at the side of the seat back 12. When one of the push buttons 13 is pushed, the associated check valve 7 is opened by means of an associated push rod 14. Therefore, the air pressure within the associated air bag 11 will be relieved through the space 1, air filter 8, check valve 7, chamber 6, orifice 15, air filter 4 and the outlet port adjacent the ball 3. It is noted that under the above conditions the port 2 is disconnected from the pressurized air source. Accordingly, by pushing selected buttons, the degree of inflation of the various air bags 11 can be controlled to suit the individual requirements.
However, in the conventional lumbar support air valve assembly described above, it is difficult to manipulate the push buttons when they are positioned on the side of the seat back. If the push buttons are provided on the dash board of a vehicle the ease of manipulation will be improved, but an extensive arrangement of air pipes is then required between the seats and the dash board for supplying the pressurized air to the various air bags. It is extremely difficult to arrange such air pipes within the limited space available.